A Basic Multiplication Question (Common Mistake)

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HermioneGranger wrote:

Hi, a desperate question.In solutions of equation, when you multiply 2(2) by two, why is the answer 2(4) and not 4(4)?

TIA

Answer:
Good question!

The theoretical reason is that if we multiply a product a(b) by two, we are actually having two copies of a(b).

Hence, 2 x a(b)= 2 times of a(b) = 2a(b) = a(2b)

For a concrete example, think about what would happen if we multiply 1(1)(1)(1)(1) by 2.

1(1)(1)(1)(1) is just 1, hence the answer should be 1(1)(1)(1)(2)=2, and not 2(2)(2)(2)(2) which is 32.

Author: mathtuition88